The House Ways and Means Committee released whistleblower testimony accusing the Justice Department of interfering in the investigation into President Joe Biden’s son, Hunter. The testimony came from two former IRS agents, one identified as Greg Shapley, who worked on the investigation into Hunter’s taxes and foreign business dealings. In their testimony, the whistleblowers described what they called a pattern of “slow-walking investigative steps” and delaying enforcement actions in the months before elections.

“Whistleblowers describe how the Biden Justice Department intervened and overstepped in a campaign to protect the son of Joe Biden by delaying, divulging, and denying an ongoing investigation into Hunter Biden’s alleged tax crimes,” Chair Rep. Jason Smith, R-Mo., said in a statement. “The testimony shows tactics used by the Justice Department to delay the investigation long enough to reach the statute of limitations, evidence they divulged sensitive actions by the investigative team to Biden’s attorneys, and denied requests by the U.S. attorney to bring charges against Biden.”

It wasn’t clear whether the whistleblower testimony amounts to internal disagreement about how to pursue the Hunter Biden investigation, or whether it was a pattern of interference and preferential treatment.

Justice Department policy has long warned prosecutors to take care in charging cases with potential political overtones around the time of an election, to avoid any possible influence on the outcome.

The department denied the whistleblower claims, saying the U.S. attorney in charge of the Hunter Biden probe — who was appointed by former President Donald Trump — had full authority over the case.

The release of the whistleblower testimony comes two days after Biden announced he will plead guilty to misdemeanor tax offenses as part of a deal with the Justice Department. The deal allows Hunter to avoid prosecution on a felony charge of illegally possessing a firearm as a drug user.

Congressional Republicans called the plea deal a “sweetheart deal” for the president’s son and another example of a “two-tiered justice system” that goes easy on Democrats. Republicans also pledged to continue their own investigations into the Biden family and what they call their efforts to trade off the presidency.

“If the federal government is not treating all taxpayers equally, or if it is changing the rules to engineer a preferred outcome, Congress has a duty to ask why and to hold agencies accountable and consider appropriate legislative action,” Rep. Smith said. “The scales of justice must not be skewed in favor of the wealthy and the politically connected.”